Naval Operations - US Civil War

Sailors and Marines on the Deck of the U.S. Gunboat Mendota - 1864 (detail)

The U.S. Navy's principal role during the American Civil War was to blockade the South's coastline and to use inland rivers to support Union Army operations. Over the course of the war, these joint operations with the Army cut the South off from outside support, gradually constricting its trade and commercial livelihood. Rapid improvements in engineering and weaponry led to the beginning of a revolution in naval technology, notably in the use of iron to fabricate the hulls of warships.

The Union's ironclad Monitor was built to counter the Confederate Virginia, an armored ship built on the hull of the former USS Merrimac. Although the 1862 battle between the Monitor and Virginia ended in a draw, this first battle of ironclads signaled a profound change in the nature of naval warfare. The war also saw innovations in mines, mine countermeasures, and submarines.

The Union Navy blockaded some three thousand miles of Confederate coast from Virginia to Texas in a mammoth effort to cut off supplies, destroy the Southern economy, and discourage foreign intervention.

The Navy joined with the Army to launch a series of major amphibious assaults, including those at Port Royal Sound, South Carolina, under Flag Officer Samuel F. DuPont, and Wilmington, North Carolina, led by Admiral David Dixon Porter (right). These successful actions sealed off Confederate blockade-runner havens, and assured blockading ships essential coaling stations and bases on the Southern coast.

Admiral David Glasgow Farragut's (right) victory at New Orleans denied Confederate egress from the Mississippi, and opened that mighty river to penetration northward by Union forces. In a giant pincers campaign, river gunboats moved north and south along the Mississippi and her tributaries.

Following the capture of strategic Fort McHenry by Flag Officer Andrew Hull Foote, one Confederate river stronghold after another fell to the combined attack of the Union Navy and Army. Vicksburg, the final bastion, was battered into submission 4 July 1863, and the Confederacy was mortally split along the vital Mississippi artery. Meanwhile in the east, the historic USS Monitor-CSS Virginia (ex-Merrimack) battle, first combat between ironclads, marked the dawn of a new era in naval warfare. The most famous of Confederate commerce raiders, CSS Alabama, Captain Raphael Semmes, played havoc with Northern shipping until being brought to bay off the French coast and sunk in a ship-to-ship
duel with USS Kearsarge, under Captain John Winslow, commanding officer.

Although Confederate forces fought valiantly throughout the war, control of the sea by the Union Navy isolated the South, and gave Northern military forces the added dimension of mobility which sea power provides.

Following the Civil War, the Navy was reduced in size until the 1880s, when the United States became increasingly interested in overseas expansion and trade. Although the Navy pioneered many technological innovations in the 1860s, navies in other countries adopted them much faster than the United States. In the 1880s the U.S. fleet remained essentially as it stood at the end of the Civil War-a force of antiquated wooden-hulled gunboats.

In the late 1880s and early 1890s the Navy began to build a fleet of new all-steel ships. The Navy's modernization and expansion in this period was spurred partly by the ideas of Captain Alfred Thayer Mahan, an American naval officer and historian who argued that control of the seas would lead to global military domination.

Charleston Harbor, S.C. Rear Admiral John A. Dahlgren (fifth from left) and staff aboard U.S.S. Pawnee (detail).

(See Bibliography below)

| Back to Timeline | or click on your browser's "back to previous page" button

Photographs: Library of Congress
Bibliography: Naval Historical Center, Washington, D.C;